Ice cream freezer



June 30, 1942.

A. H. BOILEAU ICE CREAM FREEZER Original Filed Jan. 26, 1939- 2Sheets-She et'l mvmbx cfirt/La/H Bgieaw BY ATTORNEY.

June 3Q,1i.94l2. A. H. BOILEAU 6 I ICE CREAM FREEZER Original FiledJanf26, 1939 2 Sheets-Sheet 2 Patented June 30, 1942 4 UNITED STATESPATENT, OFFICE Arthur H. Bz faz ifi zifdtf zwa, assignor toCherry-Burrell Del., a corporation rporation, Wilmington,

Original application January 26, 1939, Serial No.

252,884. Divided and this applicationDecem- .ber 26, 1939, Serial No.310,892

8 Claims. (01. 62-414) The present invention relates to an attemperingapparatus, such as confection freezers, and, is directed moreparticularly to the construction of the refrigerant evaporator orrefrigerant confining passage associated with the freezing or.

attempering chamber and to the refrigerant flow control apparatusassociated with the refrigerant evaporator for putting the evaporatorquickly into also desirable to be able to accurately control suchrefrigeration action in a minimum amount of time and with a minimumnumber of operations. Evaporators adapted or capable of such use areparticularly desirable in the manufacturing of ice cream by the batchprocess. Such outer surface of the processing chamber and the Iadjoining surfaces of the evaporator shell and particular desirabilityis brought about by the normally quick, repeated operations incidentalto the emptying of one batch and the re-loading and freezingof the nextba'tchl Such construction and the performance of such evaporatorsenables the almost instantaneous attainment of maximum efiiciency of'therefrigeration in the freezing operation.

The accompanying drawings illustrate the invention in an ice creamfreezer of the batch. type. However, the invention is not to be limitedto the specificembodiment described. The

portion of the invention pertaining to the agitator element, as shown inFigure 1, is more particularly referred to, as Well as claimed, in myco-pending application referred to above.

rator, and also utilizing the a'ffixing mans a fins on the outer surfaceof the processing chamber to facilitate the more eflicient heat transferto the refrigerant medium. An additional object is to provide anevaporator for 'a processing chamber in which the evaporator is soconstructed and arranged as to directly apply the ,volatile refrigeranttothe surface of the processing chamber in intimate con tact therewithand guide the refrigerantin a circuitous path thereabout, whereby, dueto the pressure caused by the gas of evaporation, high,

speed is attained-in the motion of the refrigerant, which high speed ofthe refrigerant causes it to pass in intimate scouring contact over thefins formed thereon .to effect thereby a separation of the liquid fromthe gaseous refrigerant and the removal of gas bubbles from the surfaceof the heat transfer elements. Such construction efiects an improvementin the rate of heat transfer from the materialsbeing treated in theprocessing chamber to the refrigerant medium circulated thereabout.

A still further'object of this invention is to provide means to delivervolatile refrigerant to the evaporator casing about. the processingchamber and to receive it therefrom whereby intermittent,- promptoperation of the refrigeration system at maximum capacity withoutdischarg- The principal object of the present invention is to provide anicecream freezer'evaporator of simple, efiicient and inexpensivedesignwherein the operator has accurate and immediate control of thefreezing process within the freezing chamber, which control ismaintainable'by a minimum of operations.

A further object of the invention resides in the method of making theevaporatorassociated ken' away section, showing the evaporator emwiththe processing chamberin which the outer evaporator shell is affixed tothe outer wall of the processing chamber in a, manner utilizingtheaflixing elements as guide means for the refrigerant being circulatedthrough the evapo-v ing-unused refrigerant to the compression may besecured, as well as to pre-cool the liquid refrigerant before it entersthe evaporator by the use of unevaporated refrigerant discharged fromthe processing chamber evaporator.

Other objects and purposesand other important features of the inventionwillbe apparent from the following description when read in connectionwith the accompanying drawings in which:

Figure 1 is a longitudinal sectional view taken vertically through thefreezer.

Figure 2 is a sectional view taken vertically through-the automaticthermal refrigerant valve for the freezer.

Figure 3 is an elevational view in partially brobracing the processingcylinder of the ice cream freezer. Referring to the illustrationsshowing the preferred embodiment of the invention, in which 11-lustrations likejnu'merals are associated with like elements, theinvention, which particularly pertains toan ice cream freezer evaporatorand the method of constructing the same, is illustrated in connectionwith an ice cream freezer. The ice cream freezer is supported on ahollow base I resting on adjustable feet I I. A gear housing I2 isprovided at the upper rear portion of the base and a cylinder supportingbracket I3 is provided immediately ahead of the gear housing I2,together with a cylinder supporting shelf portion i4 immediately aheadof the bracket I3, above which shelf is mounted the cylinder structuregenerally indicated by the numeral 15 applied to its envelope. Thefreezer is driven by motor l6 housed in the hollow base I0 and mountedon any suitable bracket I1. The motor I6 through a series of belts I8drives the pulley l9 which is keyed to drive shaft journaled in suitablebearings in the gear housing l2. Pinion 2| is carried by and keyed tothe drive shaft 20 and drives the.

spur gear 22 carried by a quill shaft 23 journaled in .any suitablesleeve bearing 24 mounted directly above drive shaft 29 with the quillshaft 23 opening outwardly through the front wall of the gear housingl2. Quill shaft 23 is joined at its inner end'to the adjoining freeinner end of a second axially aligned shaft-25, which is partiallytelescoped into quill shaft 23 and there supported in alignment by asuitable rotary thrust bearing 26. The outer end of the shaft 25 isjournaled in any suitable bearing generally indicated by the numeral 21.Sprocket wheel 28 fixed to and carried by shaft 23 is driven by sprocketchain 29 which passes around a driving sprocket 39 driven through theintermediacy of the disc clutch generally indicated by the numeral 3i onwhich it is mounted. Disc clutch 3| is mounted on the drive shaft 20 andactuated by lever 32 pivoted at 33 and hinged at its free end to thecontrol rod 3 f extending outwardly through the front wall of the baseI0 toward the position occupied by an operator-of. the freezer.

The inner shaft 35 and quill shaft 36 are the shafts used to drive theinner and outer elements of the reversely rotatingv agitating of theagitator mechanism within the shell 31.

The evaporator C comprises a helical evaporator passage defined on itsinner surface by the- I I1 is provided with an interruption or slot H9approximately equal to the width of the ring I I6 and immediatelyadjacentthe ends I2l of the ring-like elements H6 along the line ofcleavage of the split rings and advancing in a clockwise directiontherefrom. ..To complete the helical passage H0, defined on its innerand outer mechanism of the freezer. These shafts are tel-' I escoped attheir freeends into the squared sockets of the shafts 25 and 23,respectively, by means of which squared faces the reversely rotatingspur gear 22 and sprocket wheel 29 impart the reverse rotation to theshafts36 and 35, respec-v tively, to operate the inner and outer dasherelenients.

The processing cylinder construction comprises an outer envelope I5 andan inner processing shell 31 which serves as a refrigerated wall orcylinder housing the freezing chamber of'the freezer. The shell 31 issurrounded by a re-' frigerant evaporator C in intimate contacttherewith and spaced from envelope I6, in which space a satisfactorycover or insulation 33 is provided. Shell 31 is provided at its frontend with an annular head 39, and at its opposite end with a centrallyapertured head 40. Heads 39 and 40 are aflixed to shell 31 and envelopeI! by any suitable means, such, for example, as welding,

and head 49 is rigidly affixed to the cylinder support bracket I3 by aseries of bolts. A removable end wall or door 4| including the usualinlet passage 42 and outlet passage 43 is hinged in the conventionalmanner to the front cylinder head 39. The outlet passage 43 is closed byvalve 44,

' and the inlet passage 42 is associated with the usual type of mixreservoir 43 through the conventional type of valve 46, all of which areclear- 1y shown vided with a conical, central, inwardly directed inFigure 1. The 'end wall 4| is pro-' nearthe second to, the last shell H3slightly passing the- 'surface by the shell 31 and the joined ring-likeelements H6, and defined along its edges by the adjacent flange H1,bafile elements I20 are provided intermediate the flanges andintermediate the adjacent slots H9. The baffle elements I20 are inclinedto the plane of the elements H6 and are mounted immediately adjacentedge I2I of each of the rings H6, having their inner edge welded totheperiphery of shell 31 and their outer edge welded to and joining theangularly cut ends I2I of the ring H6. .The forward end of eachbafileelement I29 is joined to the end of a flange H1 defining the lower edgeof the associated slot H9 immediately ahead of the baflle element, andthe rear edge of each baflle I20 is joined to theadjacent end ofa flangeH1 defining the upper edge of the adjacent, rearwardly positioned slotH9. By so joining the opposite ends of adjacent flanges H1 the helicalpassage H9 intermediate adjacent portions of the flange I I1 is defined.The helical passage H0 is provided with an inlet port III at its frontupper end and discharge port H2 at its lower opposite end. Liquidrefrigerant is supplied to inlet port III through conduit H3 affixed tothe outer surface of the evaporator C', and communieating with conduit93 through nipple H4.

Evaporated or gaseous refrigerant is discharged from passage I III tothe discharge port H2 joined by nipple H5 to the refrigerant dischargeconduit 94.

The foremost or front shell H6 is also pro-v vided with an inwardlyturned flange H1 at its front edge H8 as well as its rear edge, both ofwhich-flanges H1 are welded tothe outer periphery of shell 31 to theirinner edges to complete the enclosure of passage H0. To form acontinuous helical passage utilizing the annular space between theshell-like structures H6 and the shell 31 when assembled as justdescribed.

each flange H1, excepting the front flange of the: front shell and theflange oftherear shell, is providedwith a slot or laypass H9, as justdescribed, joining the annular space on either side of the slottedflange H1. These slots are of approximately the same length as the widthof the shells H 1 and are arranged in-staggered relation, progressinguniformly rearwardly and downwardly with the slots of the first shell H6top of the shell 31, and the slot in the lower portion of the shell 31.To complete the helical passage H0, baffle means I23 are pro-- bearingsupport 41 which supports the front end vided intermediate adjacentflanges II! at an incline to the axis of the shell 6, joining the loweredges of a slot H9 with the upper edge of the adjacent rearwardlypositioned slot- II9 as just described. The baflle means I20 in theforemost and rearmost shells H6 are joined at their extreme ends to theunslotted outermost flanges III of evaporator C, and are inclinedsimilarly to the remaining bafiles I20. Bafiles I20 are welded at theirrespective ends tothe adjoining flanges Ill, and at their inner andouter edges they are welded to the shells 3! and H6, respectively. v

The baflie I20 in the foremost shell is positioned immediately below therefrigerant inlet port III in such a manner as to cause the liquidentering therethrough to flow in a counterclockwise direction throughthe annular passage formed by the foremost shell I I6, thence throughthe slot H9 joining the passage bounded by the two foremost shells,thence in a counter-clockwise direction around the portion of thehelical passage .bounded by the second shell IIB due to the positioningof the second baffle I20, and thence similarly through the remainingshells I I6 until the refrigerant reaches the discharge II2 in a gaseousstate.

,The agitating, whipping, scraping and unloading mechanism comprisingpart of the ice cream freezer shown in Figure 1 is set forth in detailand claimed in my co-pending application referred to previously.Generally speaking, the agitator shown in Figure 1 consists of inner andouter rotary elements. A front spider 55, by means of a bushing I2,supports the front end of the agitator mechanism on the shaft 35 whichis provided at its front end with a stud bearing 63 to engage acomplementary bearing seat in the freezing chamber door 4|.

Similarly, a rear spider co-acts with a drive shaft to support the rearportion of the agitator assembly. The outer agitator element, inaddition to being provided with scraping blades, is

also provided with unloading bars 53 carrying the angularly disposedunloading wings 54. The inner agitator element is provided -with twosets of beater blades 66 and 81 alternately arranged on a supportingshaft and at'an angle of ninety degrees one to another. Whipping rods 68are carried by the beater blades and are, anchored at their rearextremities in a whipping rod support or'spider I0.

In this divisional application some of the figures of the parentapplication have been appropriated and consequently the identifyingnumbers 49 to 81 inclusive and 106 to 109 inclusiveshown in the parentcase have not been referred to as they pertain primarily to the agitatorelement which is covered in detail in the parent application.

It is, .of course, obvious that the evaporator 88 through conduit 89,thence through conduit 89' to an automatic liquid refrigerant flowregulating valve 90 to a control valve 9| through conduit 92, and thencethrough the special evaporator connection 93 from which it passes As amatter of safety, a .poppet valve 96, con 7 ventionally referred to as asafety valve, is joined The automatic thermal liquid flow valve 911, asI illustrated indetail in Figure 2, is in the re-- frigerant supply lineand is of the commercial type offered on the market under the trade markC may be supplied with other types 'of cooling agents to eifect asatisfactory operation of the ,freezing processes within'the shell 31.However,

the illustrations clearly set out. a portion of an ammonia absorptionsystem and the controls therefor.

In'the preferred embodiment of the invention supplypipe 83, from whichit passes through a coil 84 of the pre-cooler 85, thence through aconduit 86 to a needle valve BI'provided with a bypass through whichbypass the liquid may pass during normal automatic operation to valveoffAlco, and the details thereof do not form a part of this .invention.Valve will be described only sufliciently to indicate. that the liquidpassing through the valve is regulated by a conical valve 90 seating inaco'nical valve seat in the flow passage I00. The movement of the valve98 is controlled through valve stem IOI which is fixed to aspring-loaded diaphragm I02 actuated by the pressure exerted upon it bythe fluid in tube I04 communicating with the thermal-sensitive bulb I03mounted in heat exchange relation on the exhaust conduit 94.

' In the event that it is desired to manually operate the evaporator C,the valve 88 ahead of the automatic thermal valve 90 is closed and theneedle and bypass valve 81 is adjusted to regulate a flow of liquidrefrigerant to the conduit 92 as desired through the conduit I05connected to one of the discharge ports of the needle and bypass valve81. The inlet port of valve 81 is associated with the beforementionedbypass, form ing a part thereof, which bypass is not shown but isconstructed inaccordance with convenusing the manual controls as setforth. Such manual control, forwhich the liquid refrigerant would besupplied through bypass I05, may also be used when a degree ofrefrigeration is desired outside of the scope of that permitted by theuse of the automatic valve 90.

'It will, of course, be evident that some of the chief advantages of thepresent invention reside in the evaporator per se and the method ofconstructing'the evaporator *C and the result 'in'- herent in suchconstruction, as well as the general arrangement and system whereby therefrigerant applied to the processing shell 31 is readily controllablein the desired manner, as

spaced relation one to another, staggered rearwardly and downwardly asshown in Figure 10. The baffles I20 as a group extend rearwardly anddownwardly in uniformly spaced staggered relation one to another in asomewhat helical alignment with the foremost b aflies I20 positionedapproximately at the top of the forward end of the shell 31. Therearmost baflie- I20 is positionedapproximatelyat the bottom of the rearportion of the shell 31. The front discontinuous or split ring H6 havingan inwardly directed flange H1 at both of its edges is next superimposedover the forward end of the shell 31 with the ends I2I of the split ringH6 embracing the front baflle I20. The edges; of the inwardly turnedflange I I1 of the front ring H6 are each welded to the periphery-of theshell 31 and the ends I2I of the ring H6 are joined to the outer edge ofthe baffle I20 and the ends of the bafile I20 are each welded to theadjacent flange H1. The lower end of the rear flange H1 of the frontring H6 is welded to the front edge of the second baffle element I20positioned immediately adjacent the rear edge of the front ring I I6.The second ring H6 is then superimposed over shell 31 with the ends I2Iof the second ring H6 embracing the outer edge of the second baffle I20and having the front edge I I8 of the second ring H6 abutting againstthe rear edge of the frontelement H6. The front edge H8 of the secondelement I I6 is then welded to the rear edge of the first element H6 andthe ends I2I of the second element H6 are Welded to the'upper edge ofthe second element I20. The ends of the flange H1 of the second elementH6 which defines the top edge of the slot H9 in the second element H6 isthen welded to the rear edge of the second bafiie I20 and the other endof the same flange H1 is welded to the front edge of the third baflleI20. The third and other elements H6 are mounted on shell 31 in likemanner with the exception of the last and rearmost element H6 which isnot provided with a slot I I9 in its flange I I1. In the instance of thelast ring-like element H6 the rear flange H1 is welded to the she1l-31throughout its entire length which in this instance extends throughoutthe entire length of element H6 from each of the edges I2I thereof. Theunique method of constructing an evaporator for an ice cream freezer, asjust described, forms a passage H which is made continuous throughoutall of the elements H6 by providing connecting bypasses in the form ofslots H9 in the flanges H1 intermediate any two adjacent hoop orshell-like elements H6 so associated with defining baflles I as todirect the refrigerant flowing through the passages H0 in a circuitoushelical path in intimate contact with the outer periphery of thefreezing shell 31. Due to the welding of the inwardly directed flangeII1 to the outer surface of the shell 31, the flanges H1 in actualityconstitute heat exchange fins extending-into the evaporator C, therebygreatly increasing'the heat transfer efficiency of the evaporator due tothe inherent advantages incidental to the structure of the evaporator,whereby the efficient heat transfer surface has been increased.

In the operation of the freezer, ice cream mix supplied to the reservoiris admitted to the 'freezing or processing chamber defined by the shell31 through valve 46 and the refrigerant is started or stopped by meansof the stop valve 9|, which valve admits the pre-cooled refrigerant fromthe automatic control valve 90 into the conduits associated with theevaporator C. Any unevaporated or liquid refrigerant which may passthrough the evaporator C passes through the conduit 94 into thepre-cooler 85'where it will be evaporated to avoid the passage of anyliquid refrigerant into the exhaust line 95 associated with thecompressor condenser unit (not shown). This arrangement is well adaptedfor the efficient and satisfactory operation of batch freezing processesin which frequent starting and stopping of the freezing operation isessential. In the-event manual control of the refrigeration system isdesired the automatic thermal control valve 90 is turned off by closingvalve 80 immediately ahead of valve 90 and opening the needle valve 81which is then used to regulate the flow of liquid refrigerant to theevaporator C through the stop valve 9|.

The foregoing detailed description has been given for clearness ofunderstanding only and no unnecessary limitations shall be understoodtherefrom. Various changes in arrangement of the various elements of thefreezer, as shown and described to explain the invention, may be made inaccordance with the common knowledge of those skilled in the art and yetcome within the scope of the invention as set forth in the appendedclaims.

The invention is hereby claimed as-follows:

1. An evaporator for refrigeration apparatus comprising a freezingchamber defined by a shell forming the inner Wall of said evaporator, anouter wall structure fabricated of contiguous sheet'metal elements, eachhaving a continuous inwardly extending flange fixed to said shellthroughout its entire length, and a continuous substantially helicalrefrigerant passage formed intermediate said shell and said outer wall,said passage being defined along its sides by adjacent flanges of saidsheet metal elements.

2. A heat exchange medium passage for attempering a chamber comprising ashell defining the outer wall of said chamber, a plurality of liquidbaflie means sealed to the outer periphery of said shell along theirinner edge, a plurality of discontinuous ring-like elements sealedtogether along their adjacent edges and superimposed over said shell toembrace said baflle means in a sealing contact along their outer edgeintermediate the ends of said ring, and uninterrupted inwardly directedflange means carried along a portion of an edge of each of said ringshaving their respective ends sealed to alternate ends of adjacent bafliemeans and having their free edge sealed to the outer periphery of said3. An ice cream freezer comprising, in combination, a freezing chamberdefined by ashell forming the inner wall of an evaporator and gasseparating means, an outer wall structure fabricated of sheet metal anddefining the outer wall of said evaporator, said outer wall structurehaving a. continuous, inwardly extending, helical flange fixed to saidshell throughout its entire length, a continuous substantially helicalrefrigerant passage intermediate said shell and said outer wall, saidpassage being defined along its edges by adjacent elements of saidhelical flange, refrigerant supply and discharge conduits associatedwith the opposite ends of the passage within said evaporator and gasseparating means,

' automatic valve means in said supply conduit for controlling the flowof refrigerant to said evaporator and gas separating means, saidautomatic valve means being responsive to the temperature of refrigerantin said discharge conduit,

and heat exchange means associated with said refrigerant supply anddischarge conduits forcated of sheet metal and defining the outer wallof said evaporator, said outer wall structure having a continuous,inwardly extending, helical flange fixed to said shell throughout itsentire length, a continuous substantially helical re- 2,2ss,oe7 I baiilemeans welded to the outer surface of said frigerant passage intermediatesaid shell and said outer wall, said passage being defined along itsedges by adjacent elements of said helical flange,-

refrigerant supply and discharge conduits associated with the oppositeends of the passage within said evaporator and gas separating means,automatic valve means in said supply conduit for controlling the flow ofrefrigerant to said evaporator and gas separating means, said automaticvalve means being responsiveto the temperature of refrigerant in saiddischarge conduit, and heat exchange means associated with saidrefrigerant supply and discharge conduits for evaporating anyunevaporated refrigerant discharged from said evaporator and gasseparating means.

5. An evaporator and gas separator for an ice cream freezer comprising afreezing cylinder, a plurality of baflies welded to the .outer surfaceof said cylinder, and-a plurality of fabricated sheet metal elementssuperimposed over the outer surface of said cylinder in such a mannerthat each of. said elements embraces one of said baiiie means, saidfabricated sheet metal elements being sealed one to another and to saidbaiiie means to form a segment of a fluid flow passage, said fluid flowpassages communicating with each adjacent flow passage in such a manneras to form from. the segmental fluid flow passage a series-connectedrefrigerant flow passage encircling said freezing cylinder.

6. An evaporator and gas separator for an ice cream freezer comprising afreezing cylinder,

cylinder, and a discontinuous metal ring-like element superimposed oversaid cylinder to embrace a bafile means intermediate the ends of saidring-like element, said ring-like element having its edges welded to theouter periphery of said cylinder and to the top edge of said embracedbailie means.

7. An articlev of manufacture' comprising a freezing cylinder, aplurality of baiile means welded to the outer surface of said cylinder,a

discontinuous metal ring-like element superim-' posed over said cylinderand embracing one of said baflie means intermediate the ends of saidring-like element, said ring-like element having its edges welded to theouter periphery of said cylinder and to the top edge of said embracedbaflie means, and a second ring-like element superimposed over saidcylinder and abutting against said first mentioned ring-like element andembracing one of said bafiie means intermediate its ends, said secondring-like element being welded to said first ring-like element along theline of contact therewith and having its free edges welded to saidbaiiiemeans embraced thereby and to said cylinder.

8. In an ice cream freezer, a cylinder for containing material fromwhich heat is to be extracted, a plurality of outwardly extending finshaving their inner edges fixed to the outer periphery of said cylinderin intimate permanent union therewith and arranged in side by side orderone with respect to another, a laterally disposed outer portion on eachfin overlying the space between two adjacent fins and flxed to theoutwardly extending portion of the adjacent fin in intimate permanentunion therewith, the outwardly and laterally extending portions of saidadjacent fins and the outer periphery of said cylinder, when joined inintimate permanent union one with another, forming a fluid passageway,and fluid passage connections between ad- Jacent fiuid passageways soarranged as to form a hello-like circuitous refrigerant passageencircling said cylinder, whereby the heat exchange between saidcylinder and refrigerant flowing within said circuitous passage isimproved.

ARTHUR H. BOlLEAU..

